Documentation Consistency (rules)

I'm seeing various 'standards' applied throughout the builtin library 
documentation. I'd like some guidance on which way is the 'official' 
way to do things in each case.
1) Parameters in methods: italicized or not?
I'm seeing parameter names both italicized (e.g. Matrix) and not (e.g. 
File). Which is it?
        method_name( param1, param2 )
        method_name( <i>param1</i>, <i>param2</i> )


2) Return type indication: -> or =>?
Only currently possible in the C call-seq: documentation, I'm seeing 
both -> and => used. (e.g. File#chmod vs. File#chardev?)
        method_name( ... ) -> returntype
        method_name( ... ) => returntype
        method_name( ... ) -> <i>returntype</i>
[too bad we can't use &rarr; or &Rarr; ... maybe RDoc could swap these 
out in the HTML documentation?]
3) Empty parameter list ... ()  or not?
        method_name => returntype
        method_name() => returntype


4) Instance present in instance methods?
        method_name => returntype
        myclass.method_name => returntype

[The latter only being possible within call-seq: calls, again, unless 
RDoc parsed .rb files and inserted a ClassName.downcase in front of all 
instance methods.]
5) Describing the parameters: formally or inline?
I'm personally a fan of explicitly describing each parameter at the 
start of the method documentation, e.g. 
http://phrogz.net/RubyLibs/rdoc/classes/ValidForm.html#M000054
Should this sort of thing be formally suggested, or is it up to each 
person to decide if the parameter list warrants being laid out like 
this vs. just describing it inline, such as Bignum#remainder does? 
(http://www.ruby-doc.org/docs/rdoc/1.9/classes/Bignum.html#M000841)
--
(-, /\ \/ / /\/
"A foolish consistency is the hobgoblin of little minds."